Collapsible structure



FIG. 1 is a perspective view of the embodiment;

FIG. 2 is a right side elevation view, the left side elevation viewbeing identical;

FIG. 3 is a front elevation view, the rear elevation view beingidentical;

FIG. 4 is a top plan view; and,

FIG. 5 is a bottom plan view.

CLAIM The ornamental design for a collapsible structure, as shown anddescribed.